Everyone could always use a little extra money, right? That's especially true if you've recently purchased an airline ticket. Flights are usually extremely pricey, even if you're flying coach, but that's the nature of taking to the friendly skies.

But if you've flown on a major airline in the last few years, you may be entitled to a little pocket cash that could be coming back to you.

Thanks to a recent class-action lawsuit settlement, you may be entitled to some cash from the four largest aircraft carriers: American, United, Delta and Southwest Airlines, all involved in the suit. Southwest and American Airlines have agreed to a settlement thus far, but litigation is still ongoing against Delta and United.

Does a major airline owe you money?

The lawsuit is classified as an antitrust case, and revolves around claims that these airlines worked to conspiratorially and artificially limit domestic fight capacities by charging more for plane tickets. For consumers, this means that anyone who purchased tickets may have paid higher prices when there was no technical or legitimate basis for doing so.

You can check out the official settlement website, which features answers to any questions you may have about the lawsuit, but these are the current requirements for you to be eligible for money back on your purchases:

Purchased a flight within the U.S., its territories and the District of Columbia

Purchased from the four major airlines listed or their subsidiaries and affiliates, including US Airways and Continental

Purchased an airline ticket between July 1, 2011, to Dec. 20, 2017, for Southwest Airlines and between July 1, 2011, to June 14, 2018, for American Airlines

Unfortunately, there aren't any details as to how much money you may potentially be entitled to. If you're interested in finding out more, you can call a special hotline at 1-866-459-3634 to see if you qualify for cash back in the settlement or write to Domestic Air Settlements at info@DomesticAirClass.com.

In the meantime, you may want to save all those receipts for your airfare. You never know what kind of reward may be coming back your way.

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